stare



(No Model.) 3 Sheets-Sheen.

Ea Tl DENTAL ENGINE.

w 1 MW! 9 m 2 m5 y a w M 0 d 6./ w v M, m P h B Di 3 V h i H a W M A n m .8 S 7 E .2 m. .d d y N. PEYERS. Pholo-Lilhogmphcn Wnmngmn. D C.

(N0 Mbdel.) 3 Sheets-Sheet E. T. STARR.

DENTAL ENGINE.

Patented May 29,1883. .2.

EEEEEEEEEEEI INVENTOR B /1 .dttorneys 74$ WITNESSES r4. PETERS. Pnbmmm n w. Wnhingmn, n. c.

(No Model.) '3 sheets sheet a.

E. T. STARR.

DENTAL ENGINE.

No. 278,464. Patented May 29,1883.

\ By hi .dltorneys N. PETERS. PholvLhhogr-lphur. Wflshinghm. D. c.

l 25 a counter-balance or spring.

UNITED STATES P TENT OFFICE.

. ELI rs'rAaB, F PHILADELPHIA, PENNSYLVANIA, Assie oR are THE s. s.

WHITE DENTAL MANUFACTURING COMPANY, OF sAME PLAoE.

DENTAL- ENGINE.

SPECIFICATION forming part of Letters Patent No. 278,464, dated May 29, 1883.

Application filed February 13. 1883. (No model.) Patented in England August 13. 1879, No. 3,262.

' To all whom it may concern Be it known that I, ELI T. STARR, of the city and county of Philadelphia, in the State of Pennsylvania, have invented certain new and'useful Improvements in Dental Engines,

of which the following is a specification.

My invention relates more especially to improvements upon the well-known S. S.White dental engine. That engine consists of a sup- [0 porting base or tripod, upon which is pivoted an upright arm carrying a driven spindle and flexible shaft, connected therewith, which communicates motion to the operating-tool, power beinglimparted to the flexible shaft from a i 5 foot-treadle, also mounted on the base. The flexible shaft is enveloped and protected by a flexible sheath or cover secured to or projecting from the head or upper end of the enginearm, which arm has the capacity of rocking backward and forward, whereby an increased range of movement is given to theoperatingtool over that afforded by thelength and flexure of thedriving-shaft, the said rockingarm being maintained in a normally upright position by l have found it desirable to give the engine base or tripod the capacity of being tilted or inclined, so as to throw or bring the head or upper end of the engine-arm in front of or toward the patient, irrespective of the rocking movement of said arm, and without bringing the base or treadle inconveniently close to the patient, which capacity affords great freedom to the flexible driving-shaft and to the flexible sheath or 5 cover when that is employed to envelop and protect the said shaft. t The treadle, being mounted upon the base or tripod, is also inclined therewith, thus presenting. the treadle to the foot in a proper manner to enable it to 4.0 be worked by the operator with ease and comfort, the foot not being compelled to constantly maintain and operate in an unnatural and strained position.

Toattain these ends I have devised improve- 4 5 men'ts constituting my present invention,

which improvements consist, first, in providing the ba'sefor tripod of adental engine with an inclining device or mech anism,whereby the base maybe tilted and the arm of the engine o thrown out of the perpendicular; and, secoudly, in providing the base or arms of the tripod of a dentalengine with devices or mechanism capable of being adjusted either to incline the base and tilt the engine-arm carried side of the perpendicular,) or to allow said base or tripod to rest evenly and squarely uponthe floor or supporting-surface.

My present invention also consists in certain new combinations of devices, particularly recited at the-close of this specification. I

The accompanying drawings show a dental engine embodying all my improvements in the best way now known to me. Obviously, how ever, some of my improvements may be used 6 without the others, and in engines differing somewhat in their details of construction from that therein shown.

Figure l is a side elevation of my improved f engine with the top portion or upper works thereof broken off and brought down to one side to show the whole apparatus; Fig. 2, a view thereof from the back of the engine; 7 Fig. 3, a plan or top view of the base or tripod with the treadlepivoted thereon, the standard and pitmau beingin' section on the line 3 3 of Figs. 1and2; Fig. 4, a bottom view of one of the arms of the tripod-base, and Fig. 5 a longitudinal section therethrough on the line5 5 of Fig. 4; Fig. 6, a view of a portion oft-he fixed standard which rises from the base of the rocking arm, and of the mechanism for varying the normal position of said arm, partly in section on theline 6 6 of Fig. 7; and Fig. .7, a'

paratus on the line 7 7 of Fig. 6.v

The base, tripod, or stand A is provided with a'fixed upright or standard, a, forming part of the base, preferably the upper end of which is forked or divided for-the reception of c the driving-pulley or fly-wheel B, thejournal or trunnions of which turn in suitable bearings-or boxesin said standard in the usual manner. A driving-crank, b, is attached to oneend of the pulley journal or axle in this 95 instance, and is connected by a plate-spring pitman, G, preferably, with the tre'adle, pedal, or foot-board D,'pivoted or jointed upon one arm of the tripod or upon the base, as usual.

thereby in ditt'erent directions, (or to either 55 vertical section through aportioni ot" the ap- The forked or divided end of the standard is 1200 also provided, outside the pulley, with trun nions or pivots a a for the reception of the forked lower end of the engine-arm E, which is also of well-known construct-ion, carrying upon its upper end a driven pulley and its spindle, to which latter the flexible drivingshaft is connected, as usual. Suitable beltconnections pass from the driving to the driven pulley. The flexible shaft or powerconveyer and itsenveloping protecting-sheath, when the latter is used, are similar to those employed in the S. S. White dental engine, hereinbefore referred to, and substantially similar to those shown in Nelson Stows Reissued Letters Patent No. 8,607, of March 4, 1879. the original of which is dated August In order to give the tripod or base the capacity of being tilted or inclined at pleasure in difl'erent' directions, so as tothrow or bring the head or upper end of the engine-arm in front ofor toward the patient or out of the perpendicular, irrespective and independently of itsrocking movement upon the base, and without at the same time necessitating bringing the base or treadleinconveniently close to the patient or operating-chair, and, furthermore,-

also, in order to incline the pedal, treadle, or foot-board so that it may be operated,when 0 the foot is thrown out, with ease and comfort, I provide the baseor tripod with mechanism consistin g, by preference, of pivot-pieces or toes A A, which are mounted or attached preferably one to each arm ofthe tripod opposite 5 the arm or portion upon which the treadle is mounted. These pivot-pieces are. acted upon by retaining plate-springs a (1 as clearly shown in Figs. 4 and 5, said springs acting to maintain the pivot-pieces in their adjusted po 0' sition, whether that be a position to tilt the base or otherwise. The toes or pieces are pivoted, when the tripod form ofbase is employed, by, preference in the ends of the arms of the tripod,so that when thrown out or adjustedin line with said arms the base is permitted to rest squarely and evenly upon the floor or supporting-surface, but when moved, rocked, or adjusted inwardlyat right angles, or nearly so, to said arms, raise that portion of the tripodbase to which they are pivoted, consequently tilting or inclining the base, its standard, and the engine-arm, with its appurtenances, together with the treadle. It will be obvious that when both the inclining toes or devices are adjusted to tilt the base said base will be tilted in the direction of the length of the treadle, while if one only at atime of the toes be used or adjusted the base will be tilted sidewise, whereby I am enabled to incline or tilt the base and its appurtenances in diiferent directions or to either side of the perpendicular, as may be desirable or necessary. The upper end or-head of the engine-arm may therefore be brought, if the en- 6 5 gine be in proper position, toward or in front of the patient, affording great freedom of movementto the flexible driving-shaft and to its enveloping sheath or cover, which is a de'sideratum ot' muchimportance in the perfect working of dental engines.

It will be obvious that various changes in the details of the inclining or tilting devices or mechanism will readily suggest themselves to skillful mechanicians without departing from my invention. For instance, the toes or inclining devices shown may be made in sections longitudinally extensible, so as to incline the base and engine-arm to a greater or less degree.

To control the rocking movement of the engine-arm or to return it automatically to and maintain it in a normal position, various counter-balances have been employed, the best form of which is considered to be a spring the tension of which, as soon as the force exerted to rock or deflect the arm is removed, returns said arm to its normal position. The return ing or counterbalancing springs (both spiral and plate springs) have been applied in various ways.

lnorder to enable the normal position ofthe engine-arm relatively to the base to be varied at pleasure, and also to permit this variation in normal position without destroyingthe rocking capacity of the arm, I employ in this, instance a plate,F, pivoted atf concentrically with the rocking arm, and secure to said plate one end of a plate-spring, G, the other end of which is provided with a yoke or loop, g, through which the rocking arm passes, said yoke being the means by which the spring acts upon the arm in'the example shown. The plate F is provided with a curved slotJ", concentric with its pivot, through which a setscrew or lockingbolt passes into a socket formed in the standard of the base or tripod. By tightening this set-screw or bolt the plate may be locked in any position desired in its range of movement around its pivot permitted by the slot, and consequently the angle ofthe arm varied at pleasure, which angle will be the normal position of the rocking arm, inasmuch as it will be so maintained by the spring, and automatically returned, when deflected or rocked, to that position when the strain is removed by the force or tension of said spring.

By the construction and organization above described I am enabled to secure the platespring which retains the rocking arm in its normal position to the base, while allowing it to act upon said arm above the base, and thereby avoid the necessity of extending the engine-arm or a portion thereof below its pivots to be acted upon by the spring, and, furthermore, obtain a compact arrangement of parts.

The branch of the forked rocking arm E next the adj usting-plate F, it willbe observed, is provided below its pivot with depending ears or lugs e e, which overlap or pass down upon both sides of the upper contracted portion of said plate, which construction is for the purpose of limiting the range of movement of the rocking arm, no matter in what IOC.

Iio

hdrmal position it may be placed by the adtreadle mounted on' the base, whereby said justment of the plate F, inasmuch as said lugs comein contact, when the arm is rocked, with the sides of the plate, which plate is fastened firmly to the standard of the base'by its securin g device. It will be obvious that the capacity of variable change in normal position i may be given to the rocking arm in various ways, which will readily suggest themselves to skilled mechanics upon reading this specification, without departing from my invention.

I have hereinbefore stated that the enginearm is of well-known construction, andI prefer it to be composed of sections, as in the before-mentioned S. S. White engine, one of which is extensible on the other by screwthreads preferably or equivalent means,and

.lockedtogether, when desired, by a suitable plication the subject-matter claimed in the first division of said original application, which was filed June 17, 1879, and patented September 2,1879, as No. 219,320; nor do I claim herein any patentable subject-matter shown, described, or substantially indicated in my said original application, except that particularly comprehended in the following clauses of claim.

I reserve as the subject-matter of my said original application any and all patentable subject-matter therein indicated which is not claimedin my said patent of. September 2, 1879, nor included inthe claims of this appli; cation. This application is therefore restricted to the subject-matter claimed herein, which I' stateas follows: I

1. The combination, substantially as hereinbefore set forth, of the dentalaengine base, its arm, and mechanism for inclining or tilting said base.

2. The combination, substantially as hereinbefore set forth, of the dental-enginebase, provided with a device or mechanism to tilt or incline it, with the engine-arm capable of movement out of the perpendicular.

3. The combination, substantially as hereinbefore set forth, of the base, its inclining or i tilting mechanism, the engine-arm, and the base, arm, and treadlemaybe tilted or inclined together.

4.. The combination, substantially as hereinbefore set forth, of the base, its arm, a tilting device to incline said base, and mechanism to lock the tilting device in position as ad .justed.

5. The combination, substantially as hereinbefore set forth, of the dental-engine base, its arm, and devices ormechanism to incline the base in diiferent directions, whereby the said arm may be moved to eitherside of the perpendicular by the tilting of the base.

6. The combination, substantially as hereinbefore set forth, of the base, the engine-arm capable of rocking on said base, mechanism to maintain said arm in different positions relatively to the base, and devices'or mechanism to tilt or incline said base.

7. The combination, substantially as hereinbefore set forth, of the base, the engine-arm rocking thereon, and the device or mechanism to tilt or incline the base at an angle to the plane of the independent rocking movement of the said arm. V

8. The combination, substantially as hereinbefore set forth, of the base, its tilting device, the mechanism for locking the tilting device to the base, the rocking engine-arm, and

the mechanism for normally inclining the engine-arm relatively to the base.

9. The combination, substantially as hereinbefore set forth,of the base,its tilting mechanism, the driving-pulley, the engine-arm, the driven pulley, and the flexible shaft.

10. The combination, substantiallyas hereinbefore set forth,of the base, its tilting mechanism, the driving-pulley, the treadle,the rocking engine-arm, the mechanism for changing the normal position of said arm, the driven pulley, its spindle, and the flexible driving ELI 1. STARR.

Witnesses: I

GEORGE P. MORGAN, WM. J. PEYTON. 

